1. Field of the Invention
This invention is directed to a method of producing a charcoal product from a combination of wood and the deinked sludge waste from the manufacture of reconstituted paper.
2. Description of the Prior Art
It is well known that the making of charcoal consists in the destructive distillation of wood to drive off the volatile hydrocarbons, pyroligneous acid, and tar. It is also well known that the making of paper begins with pulp for its cellulose content. The cellulose fibers from wood are used mainly in two forms; one is ground wood or mechanical pulp without purification which goes into newsprint, cheap manila paper and nonpermanent tissue, the other is chemical pulp such as soda process pulp, obtained from digestion of wood chips, or sulfite process pulp obtained by digestion with a solution of calcium disulfite containing free sulfur dioxide, or sulfate process pulp in which sodium sulfate is added to the caustic liquors but is reduced by the carbon present to the sulfide which becomes a digesting agent. Whichever paper making process is employed, the pulp needs to be treated to remove the printing ink, and that results in the formation of a deinking sludge which is considered as a throw-a-way material that is regarded as a pollutant.
Since the making of charcoal uses a wood material, and the sludge discharge in the paper making industry comes from a wood fiber, it has been found that the deinking sludge when properly dewatered can be used in the making of charcoal, thereby using up the sludge, rather than collecting it for disposal as a throw-a-way environmental pollutant.